Æ32 - Valerian and Gallienus ΕΠΙ Ϲ ΒΑΛ ΑΡΙϹΤΟΜΑΧΟΥ ΟΜΟΝΟΙΑ ΜΥΤΙΛΗΝΑΙΩΝ ΚΑΙ ΠΕΡΓΑΜΗ/ΝΩΝ

This coin documents the homonoia — formal friendship — struck between Mytilene on Lesbos and Pergamon, one of dozens of such alliance coinages produced by Greek cities under Roman rule during the mid-third century. The magistrate named in the legend, Bal. Aristomachos, is otherwise unattested, which is typical for provincial officials of this rank whose careers left no other surviving record. Homonoia issues between cities were often prompted by commercial agreements, shared cult observances, or the need to smooth over long-standing civic rivalries — the specific occasion here is unrecorded.